Refrigerant compressors having a refrigerant suction ring valve integral with each piston have been successfully used for many years. Recently, the use of new refrigerants, coupled with more demanding performance requirements, have produced pressure and temperature conditions which, in certain instances, have resulted in premature failure of the suction ring valve. The exact cause and solution have not been readily apparent, as evidenced by experimental changes to the suction valve structure which have been tried but which have not produced the desired improvement.